Ladder for toy fire engine

ABSTRACT

An extension ladder for a toy fire engine having one end pivoted to the body of the engine for raising and lowering of the ladder about a horizontal axis, a crank and gear means acting between the body and ladder for effecting said movement, said crank and gear means including a spring means yieldably retaining gears in meshing engagement and allowing said gears to disengage when the ladder is forcibly moved about said axis to prevent breakage of the crank and gear means. The base section of the extension ladder is formed of flexible material and is disposed in a track and trained over a reel to be wound outwardly or inwardly to respectively extend or retract the ladder.

llnited States Patent [191 Zbikowski et al.

[ LADDER FOR TOY FIRE ENGINE [75] Inventors: Theodore H. Zbikowski, Plymouth; Ronald R. Pauly, Mound; Lee J. Pfeilsticker, Long Lake, all of Minn.

[73] Assignee: Tonka Corporation, Minneapolis,

' Minn.

[22] Filed: Feb. 14, 1972 [21] Appl. No.: 226,095

[52] US. Cl. ..46/215 [51] Int. Cl. .....A63h 17/08 [58] Field of Search ..46/202, 207, 215

[56] References Cited FOREIGN PATENTS OR APPLICATIONS 893,324 7/1953 Germany .46/2l5 829,723 2/1952 Germany ..46/215 Primary Examiner-Louis G. Mancene Assistant Examiner-J. Q. Lever Attorney-Carlsen, Carlsen & Sturm 5 7] ABSTRACT An extension ladder for a toy fire engine having one end pivoted to the body of the engine for raisingland lowering of the ladder about a horizontal axis, a crank and gear means acting between the body and ladder for efl'ecting said movement, said crank and gear means including a spring means yieldably retaining gears in meshing engagement and allowing said gears to disengage when the ladder is forcibly moved about said axis to prevent'breakage of the crank and gear means.

The base section of the extension ladder is formed of flexible material and is disposed in a track and trained over a reel to be wound outwardly or inwardly to respectively extend or retract the ladder.

3 Claims, 6 Drawing Figures PATENTH) W29 I973 SHEET 1 BF 2 1 LADDER FOR TOY FIRE ENGINE BACKGROUND OF THE INVENTION Toy fire engines may be provided with extension ladders simulating their full sized operative counterparts. Generally, such ladders angle upwardly from the truck body with the base connected to the body for movement of the ladder about both horizontal and vertical axes.

It is desirable to adjust the ladder support frame between various fixed upwardly angling positions about the horizontal axis. However, because of the length of the support and the ladder the horizontal pivot is easily subject to damage when the ladder is forcibly moved one way or the other. It is accordingly common to pro.- vide some sort of underbracing structure to support the frame in adjusted position. This restricts the number of angular positions to which the ladder can be adjusted and still does not solve the pivot breakage problem.

Also present extension ladders for toy fire or police trucks generally comprise two or more rigid ladder sections which are slidably associated with each other in the same manner as their full sized counterparts with some sort of string, pulley and winch arrangement for causing the sections to be movedin relatively extending or retracting directions. This structure again is subject to ready breakage and fouling so as to make it unworkable.

The present invention solves these above-mentione problems.

BRIEF SUMMARY OF THE INVENTION An object of the present invention is to provide a toy fire truck having an extension ladder that has its lower end portion pivoted to the truck on a horizontal axis for raising and lowering movement of the ladder between different angular positions with a new and improved mechanism for raising and lowering the ladder which will gradually move the ladder in either direction and lock it in any selected position and yet which will yieldably release the ladder without breakage when the ladder is forcibly moved about the pivot.

Another object is to provide a toy fire truck with an extension ladder that can be extended or retracted by operation of a single control and which does not incorporate such elements as cords and pulleys which are subject to ready breakage.

With these and other objects in view the invention broadly comprises the provision of a gear segment on the inner end portion of the ladder with the said horizontal axis the center of the segment, and a crank worm gear meshing with the segment to move the ladder about the axis when the crank is operated, and including a spring means for retaining the worm gear in meshing engagement with the segment but adapted to yield when manual force is applied to the ladder. The ladder is further characterized by having a flexible ladder section trained over a drum and connected endwise toa rigid ladder section whereby as the drum is rotated the flexible section will be moved thereover to extend or retract the rigid section.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 2 is a plan view of the ladder mounting bracket and lower or inner portion of the ladder.

FIG. 3 is a longitudinal vertical section taken on line 3-3 of FIG. 2 showing the crank and gear means for raising and lowering the ladder in elevation and showing the ladder partially extended.

FIG. 4 is a section taken on line 4-4 of FIG. 3 and with the worm gear bracket shown in release position in broken lines.

FIG. 5 is a transverse section through the ladder mounting bracket taken on line 5-5 of FIG. 3.

FIG. 6 is a transverse section through the ladder taken on line 6-6 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now more particularly to the drawings reference numerals will be used to denote like parts or structural features in the different views. A toy fire engine truck 10 has a horizontal top wall 11 extending over the rear portion thereof. A ladder mounting bracket 12 has a base portion 14 secured to wall 11 as by a pin 15, allowing the bracket to pivot on a vertical axis.

Bracket 12 has a channel shape with transversely spaced parallel side walls 16 and 17 extending upwardly from the base 14. A ladder support frame denoted generally at 18 has its inner end portion 19 mounted on crank shaft 20 which is journaled in bracket side walls 16 and 17, as best shown in FIG. 5. Frame 18 has a gear segment 22 integrally formed therewith and projecting rearwardly from the inner end 19 of the frame with the arc of the segment being about the axis of shaft 20.

The bracket side wall 17 has vertically spaced tabs 24 extending inwardly toward wall 16. A gate bracket 25 has vertically spaced flanges 26 which are pivotally connected to tabs 24 by a pivot pin 27. Bracket 25 engages a stop 28 on bracket 12 to limit its inward movement. It may, however, swing outwardly to the position shown in broken lines in FIG. 4. A coil spring 29 connects the lower flange 26 to a point on wall 16 to yieldably retain the gate bracket 25 against stop 28.

A worm gear 30 is journaled for rotation in flanges 26 and is in meshing engagement with the gear segment 22. The upper end of gear 30 carries a control wheel 31 for rotating the gear. It will accordingly be understood that as wheel 31 is turned, the worm gear 30 meshing with segment 22 will cause the frame 18 to be selectively raised or lowered about the axis of crank shaft 20. However, in the event that the support frame 18 is manually forced in a raising or lowering direction the gate bracket 25 will yield rearwardly about pivot 27 allowing the teeth of segment 22 to slip along gear 30 and prevent any breakage of the components.

The ladder support frame 18 is accordingly movable about a vertical axis 15 and about a horizontal axis 20 through operation of the control wheel 31.

Frame 18 has a track extending longitudinally along its top side formed by elongated grooves 34 opening toward each other with a rigid ladder member 35 slidably mounted therein. A drum 36 is mounted on the crank shaft 20 for rotation therewith. This drum has a plurality of outwardly opening grooves 37 which are spaced equidistantly around the periphery thereof.

The frame 18 also has a track extending along the underside thereof formed by inwardly opening grooves 38 portion of section 40 adjacent to the connection 41 extends around the drum 36 with the lower portion of this section extending outwardly along the grooves 38. To extend the ladder the crank shaft 20 is turned to rotate the drum 36 clockwise, as viewed in FIG. 1. As this occurs the flexible ladder section 40 is moved upwardly by the drum from grooves 38 into grooves 34 pushing the rigid ladder section 35 outwardly from the free end of the ladder support frame 18. When the direction of rotation of shaft 20 is reversed the flexible ladder section is withdrawn into the track formed by grooves 38 and rigid ladder section 35 is retracted into the frame 18.

While the invention has herein been disclosed as a ladder for a toy fire engine, it will be understood that the mechanism for raising and lowering the frame 18 about the axis of shaft 20 might be used with equal effectiveness on other types of toys having a vertically swingable boom. Some toys presently utilizing such a structure are backhoes, steamshovels, trucks having booms with seats mounted at the extended end for use in fire fighting, trucks carrying extendable crane type booms, etc. It will also be appreciated that the use of a flexible section comparable to ladder section 40 might be used on extendable booms as well as ladders with one rigid boom section corresponding with section 35 being telescopically slidable within another rigid boom section corresponding with support frame 18.

The construction accordingly provides an extension member for a toy truck such as a fire truck which can be readily extended or retracted as well as being movable at its base about both vertical and horizontal axes. The structure is efficient, safe, durable, and economical to manufacture.

Having now therefore fully illustrated and described our invention, what we claim to be new and desire to protect by United States Letters Patent is:

1. In a toy truck having an elongated member, such as an extension ladder, mounted thereon for vertical swinging movement,

a. a mounting bracket on the truck,

b. an elongated support frame having its inner end portion pivoted to the bracket for raising and lowering movement of the frame about a horizontal axis,

0. a gear segment on the inner end portion of the support-frame arranged on an arc having said horizontal axis as its center,

d. a worm gear journaled on said bracket for rotation on an axis perpendicular to said horizontal axis and in meshing engagement with said gear segment whereby as said worm gear is rotated the frame can be selectively raised or lowered, and

e. the worm gear mounting including spring means yieldably retaining the worm gear in such meshing engagement with the gear segment.

2. In a toy truck having an elongated extension member such as an extendable ladder or boom mounted thereon for vertical swinging movement,

a. a bracket mounted on the top of the truck,

b. an elongated extension member support frame having its inner end portion pivoted on a horizontal axis to the bracket for raising and lowering movement of the frame,

c. crank operated gear means acting between the bracket and support frame for moving the frame about said horizontal axis,

d. a crank operated drum journaled for rotation on said axis,

e. a rigid extension member section mounted for sliding movement along said frame,

f. a flexible extension member section trained around said drum and connected endwise to said rigid extension member section to extend and retract the rigid section as the drum is rotated.

3. The subject matter of claim 2 wherein said extension member sections are ladder sections and said drum is provided with a plurality of circumferentially spaced peripheral grooves for seating the cross rungs on the flexible ladder section. 

1. In a toy truck having an elongated member, such as an extension ladder, mounted thereon for vertical swinging movement, a. a mounting bracket on the truck, b. an elongated support frame having its inner end portion pivoted to the bracket for raising and lowering movement of the frame about a horizontal axis, c. a gear segment on the inner end portion of the support-frame arranged on an arc having said horizontal axis as its center, d. a worm gear journaled on said bracket for rotation on an axis perpendicular to said horizontal axis and in meshing engagement with said gear segment whereby as said worm gear is rotated the frame can be selectively raised or lowered, and e. the worm gear mounting including spring means yieldably retaining the worm gear in such meshing engagement with the gear segment.
 2. In a toy truck having an elongated extension member such as an extendable ladder or boom mounted thereon for vertical swinging movement, a. a bracket mounted on the top of the truck, b. an elongated extension member support frame having its inner end portion pivoted on a horizontal axis to the bracket for raising and lowering movement of the frame, c. crank operated gear means acting between the bracket and support frame for moving the frame about said horizontal axis, d. a crank operated drum journaled for rotation on said axis, e. a rigid extension member section mounted for sliding movement along said frame, f. a flexible extension member section trained around said drum and connected endwise to said rigid extension member section to extend and retract the rigid section as the drum is rotated.
 3. The subject matter of claim 2 wherein said extension member sections are ladder sections and said drum is provided with a plurality of circumferentially spaced peripheral grooves for seating the cross rungs on the flexible ladder section. 